vasoactive-intestinal-peptide and Cerebrovascular-Disorders

Acetylcholine and vasoactive intestinal polypeptide are not only two vasoactive agonists that predominantly induce a vasodilatation of the cerebral arteries, but also correspond to neurotransmitters that innervate the various anatomical segments of the cerebral vasculature. The distinct patterns of the cerebrovascular cholinergic and vasoactive intestinal polypeptidergic innervation, their neurochemistry, in vitro and in vivo pharmacology, as well as the putative pathophysiological implications of these neurotransmission systems are critically summarized on the basis of the most recently published literature.

Topics: Acetylcholine; Aging; Animals; Cerebrovascular Circulation; Cerebrovascular Disorders; Corpus Striatum; Dose-Response Relationship, Drug; Humans; Neurons; Rats; Receptors, Cholinergic; Sympathetic Nervous System; Synaptic Transmission; Vasoactive Intestinal Peptide

In order to study alterations of peripheral substance P (SP) and vasoactive intestinal peptide (VIP) in the immunoreactive nervous system in essential hypertension, plasma SP and VIP concentrations in stroke-prone spontaneously hypertensive rats (SHRSP) at 8, 12, 18, 28, 30, 35 and 48 weeks of age and age-matched Wistar-Kyoto rats (WKY) were measured, using enzyme immunoassays (EIAs). The mean plasma SP concentrations of SHRSP (n = 61) and WKY (n = 58) were 4.9 +/- 1.2 fmol/ml and 6.6 +/- 1.9 fmol/ml, respectively. The value of SHRSP was significantly lower than that of WKY (p < 0.01). The mean SP concentration of young SHRSP was significantly higher than those of other ages. The mean plasma VIP concentrations of SHRSP (n = 61) and WKY (n = 58) were 0.80 +/- 0.25 fmol/ml and 1.01 +/- 0.32 fmol/ml, respectively. The value of SHRSP was significantly lower than that of WKY (p < 0.01). These decreases in plasma SP and VIP concentrations of SHRSP were observed at all ages. Decreases in the peripheral release of SP and VIP from the endings of SP- and VIP-immunoreactive nerves of SHRSP were seen, and the functional involution of peripheral SP- and VIP-immunoreactive nerves in essential hypertension was suggested.

Topics: Animals; Cerebrovascular Disorders; Hypertension; Immunoenzyme Techniques; Male; Peripheral Nerves; Rats; Rats, Inbred SHR; Rats, Inbred WKY; Substance P; Vasoactive Intestinal Peptide